1. Field of the Invention
The present invention relates to a picture control device which moves and plays accumulated video content, and more specifically relates to a picture control device which moves and plays video content subjected to copy restriction by controlling the bit rate thereof.
2. Description of the Related Art
Current digital broadcasting uses an accumulation method called copy-once. Copy-once is also called “single copy permissible” or “one generation copy permissible”. With this method, at the point in time of the broadcast content being accumulated (recorded), the “single” or “one generation” is completed, and the recorded content becomes “copy inhibited” content. Accordingly, in the case of outputting broadcast content to an external recording medium, an operation called “move” is performed. That is to say, in exchange for output to the external recording medium, the original content recorded is deleted. An external recording medium is a recording area or recording medium other than the recording device wherein the broadcast content is recorded, and is not necessarily a broadcast receiving device or an arrangement set externally from the recording device.
However, with this method, if any trouble occurs during moving, there has been the possibility of the output destination content and the original content both disappearing or becoming incomplete. Also, outputting the original content to an external recording medium once but being able to store the content again in the original device has not always been possible.
There is another copy control called check-in/check-out which is disclosed in Japanese Patent Laid-Open No. 2003-132625. Check-out means that the original content which is permitted to be copied N (N is a positive number) times is copied from the recording medium wherein the original contents are recorded to other recording devices the maximum N times. In this case, the original content is not erased, and the copy control information is decremented to (N−1) times. In the event of N=0, further copies cannot be made. Also, normally, content which has been duplicated once can be played back, but cannot be copied further. Check-in means that when the copy control information of the original content is at (N−1) times, for example, processing is performed to return the content from the other recording medium to which copy has been made. In this event, the copy control information of the original content is changed to ((N−1)+1). The content recorded in the other recording medium is erased at this time.
An information transfer device is disclosed in Japanese Patent Laid-Open No. 2005-158233, where even in the event of a move performed with compression, the original information can be returned with an inverse move.
The original content is locally encrypted, and an encryption key is transmitted therewith at time of check-out. The encrypted original content cannot be played back, but will not be deleted. At the time of check-in, by moving only the encryption key, the encrypted original content is enabled to be played back, and the moved copy content is disabled for playback.
An information management method for separating and managing license information to enable content playback when content is recorded onto the HDD of a video recorder is disclosed in Japanese Patent Laid-Open No. 2006-004543. In this method, by transferring the license information and lowered-bit-rate content data and content ID to a portable terminal, the content data can be virtually moved.
However, with the information transfer device disclosed in Japanese Patent Laid-Open No. 2005-158233, and the information playback device disclosed in Japanese Patent Laid-Open No. 2006-004543, once the content is output externally, the accumulated content cannot be played back without the encryption key being returned. That is to say, if a user outputs the content externally, another user cannot view or listen to the content until the encryption key has been returned, thus causing an inconvenience. Improvements in functionality of portable terminals means further increases in opportunities for copying content accumulated in a digital television receiver, for example to a portable terminal, and viewing this out-of-doors, in the future.
With the copy controls with check-in/check-out as described in Japanese Patent Laid-Open No. 2003-132625, the above-described inconvenience does not occur, but for digital broadcast content, the copy-once restrictions generally apply.
Thus, with the present invention, in the case of outputting content recorded from a digital broadcast or the like which has copy-once restrictions to an external device, the format of the output thereof is managed. That is to say, the present invention stores how (i.e. with what resolution or bit-rate) the output (check-out) is made to which recording region or recording medium. The encrypted original content itself is then not changed, but restrictions are provided as to the playback of the original content according to the output format. Also, by returning (check-in) the output content, the restrictions for playback are lifted. That is to say, with the present invention, even in a case wherein video content is output to an external media, the original content can be viewed/listened to with restrictions as to the playback quality thereof.